Bladed discs (or blisks) such as those used in the fan and compressor sections of a gas turbine engine are typically manufactured by joining the blades to the rotor disc using linear friction welding. In this process, one of the blade or rotor disc is oscillated laterally whilst being forced against the other. This generates heat through friction which results in the joining of the two parts along a weld joint.
A burr of excess material known as weld flash is generated along the weld joint and this may extend in excess of 30 mm from the weld joint. This is shown in FIG. 1 which shows a rotor disc 1 with a blade 2 attached at a weld joint 3. Weld flash 4 extends from the weld joint 3. The weld flash is typically removed manually using a hammer and chisel prior to the welding of the adjacent blade. The use of a hammer and chisel poses a high risk of damage to the blade and also poses a health and safety risk to personnel using the tools. Furthermore, the manual nature of the flash removal does not allow accurate control of the weld flash removal.
There is the need for a process for the removal of weld flash at a weld joint that allows accurate control of the flash removal and that minimises the risk of damage to the blade and the risk of injury to personnel.